Currently, mobile robots (e.g., sweeping robots) have been accepted and actually used by more and more families. A sweeping robot may automatically return to a charging pile for charging when the power is not sufficient to continue cleaning. Conventional auto-recharging approaches of sweeping robots include: 1) a charging base emits an infrared signal; after entering into the coverage of the infrared signal in the process of movement, the robot receives the infrared signal via an infrared receiver at the front end of the robot and repeatedly adjusts the direction of motion until it contacts with a metal electrode sheet on the charging base; 2) a navigation technology is adopted; the charging base projects two beacon's faculae to the ceiling; a four-quadrant infrared receiving window is arranged at an upper end of the robot; the current coordinates and pose of the robot may be computed by converting the projected area of the faculae on a sensor into an electrical signal.